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Start PreambleStart Printed Page 78184
December 19, 2006.

Take notice that the following hydroelectric application has been filed with the Commission and is available for public inspection.

a. Type of Application: New Major License.

b. Project No.: P-2301-022.

c. Date Filed: December 15, 2006.

d. Applicant: PPL Montana.

e. Name of Project: Mystic Lake Hydroelectric Project.

f. Location: The existing project is located on West Rosebud Creek in Stillwater and Carbon Counties, Montana. The project occupies about 674 acres of federal lands in the Custard National Forest managed by the U.S. Forest Service.

j. This application is not ready for environmental analysis at this time.

k. Project Description: The existing project consists of the following: (1) a 368-foot-long, 45-foot-high, concrete arch dam/spillway; (2) 42-inch high timber flashboards on top of the arch spillway; (3) a 145-foot-long, 15-foot-high concrete core and earthfill dike with 1-foot-high flashboards; (4) Mystic Lake with a storage capacity of 47,000 acre-feet and a surface area of 446.7 acres at its normal maximum surface elevation of 7,673.5 feet above msl; (5) a 33-foot-long, 7-foot-high, by 9-foot-wide concrete intake structure at the left abutment of the dike; (6) a conduit from the intake structure to the powerhouse consisting of a 1,005-foot-long rock tunnel, a 9,012-foot-long, 57-inch steel pipeline with an inverted siphon near the mid-point of the pipeline, a surge tank, and a 2,566-foot-long by 42 to 48-inch diameter steel penstock; (7) a 60-foot-wide by 85-foot-long concrete powerhouse with two turbine-generator units with a total installed capacity of 11.25 megawatts; (8) two concrete tunnels that extend from the powerhouse into West Rosebud Creek; (9) a re-regulation dam about 1.5 miles downstream from the Mystic Lake powerhouse consisting of a 19-foot-high, 420-foot-long earthfill dike with a concrete spillway with flashboards; (10) West Rosebud Lake with a storage capacity of 470 acre-feet and a surface area of 49 acres at its normal maximum surface elevation of 6,397.4 feet above msl; (11) two 5.3-mile-long, 50-kilovolt transmission lines; (12) a 9,363-foot-long distribution line from the powerhouse to the arch dam and a 2,068-foot-long distribution line from the powerhouse to the surge tank; (13) an operator village adjacent to the powerhouse with four homes and three maintenance buildings; and (14) appurtenant facilities.

PPL Montana currently operates the project in both base load and peaking modes depending on water availability, electric demands, and existing license constraints. Typically, from mid-May to mid-August, inflows exceed the project's hydraulic capacity and the project is operated as a base load plant, continuously generating at maximum capacity. During this time, flows above the project's hydraulic capacity are captured in Mystic Lake which is gradually raised about 15 to 20 feet per month until it exceeds the project's current minimum recreation elevation of 7,663.5 feet msl. In most years, Mystic Lake is maintained about ten feet higher than the minimum recreation elevation during July and August.

After Labor Day, PPL Montana begins to slowly draft Mystic Lake, reducing its elevation by an average of 8 to 9 feet per month, until the lake is at or near its lowest elevation of 6,512.0 feet msl by the end of March. Drafting the lake permits PPL Montana to release more water into West Rosebud Creek than otherwise would be available from inflows from August through March. During the fall and early winter, PPL Montana employs limited peaking to maximize generation during high use periods, generally from 8 a.m. to 4 p.m. daily. In general, flow changes caused by peaking do not extend further than the project's re-regulation dam which creates West Rosebud Lake located about one mile downstream of the powerhouse.

l. Locations of the Application: A copy of the application is available for review at the Commission in the Public Reference Room or may be viewed on the Commission's web site at http://www.ferc.gov using the “eLibrary” link. Enter the docket number excluding the last three digits in the docket number field to access the document. For assistance, contact FERC Online Support at FERCOnlineSupport@ferc.gov or toll-free at (866) 208-3676, or for TTY, (202) 502-8659. A copy is also available for inspection and reproduction at the address in item (h) above.

m. You may also register online at http://www.ferc.gov/​esubscribenow.htm to be notified via email of new filings and issuances related to this or other pending projects. For assistance, contact FERC Online Support.

n. Procedural Schedule: The application will be processed according to the following Hydro Licensing Schedule. Revisions to the schedule may be made as appropriate.